Sooner or later, all wells at certain periods in their lives will be abandoned and require plugging. Inactive, improperly abandoned wells can become a significant threat to the environment by polluting groundwater quality and/or marine ecosystems.
Oil companies’ onshore field experiences show that wells abandoned a few years ago sometimes exhibit leakage due to a lack of plugging set-up in wells. While it may be no problem to perform a remedial job in an onshore field (only expenditures could be critical), doing an offshore remedial job could have a dramatic cost effect. Consequently, abandonment of offshore wells must be considered carefully.